Thought I had mentioned someone talking about dual vs single pattern selection in a paper or video. It was in a video I saw several months ago. The guy is talking about the selection based on on Exh/Int flow ratio of the heads. His breaking point was 75%. Anything above go single pattern, below go with dual pattern profile. Think it may be his personal rule of thumb. Don't know anything about the guy, just ran across his 2 part video on cam selection. He does mostly talk about Fords and Chevys but I would think the basis of air flow would apply across the board. He did say cam lift should be determined by head flow but I think that was in part 1 of the series.
Folks here may have already seen this guys videos. Here is the link to video part 2. He talks about the profiles at ~ t=16:53. At 0.500" lift the ProMaxx 171 flow chart from the manufacturer puts it at about 73.7%. 0.600" lift puts the ratio at about 76%. I was thinking of between 0.491-0.502 or in that ball park based on ProMaxx flow chart. Again, I am learning about more of the finer details matching parts of engine building, so I'm not taking everything I find on YouTube as gold. Parts ain't cheap these days but I guess "cheap" is all relative to the size of your bank account! Lol.
I have seen and heard a bunch on this topic proving one over the other a few times and I think it just “depends.”
To be honest, for myself, I do t care anymore. I’m just going to play with stuff and find out what works (for me) & what doesn’t work (for me) in various combinations and settings.